Purdue Scientists Uncover What Makes Soybeans Tick

Massive project maps soybean genome.

Published on: Jan 18, 2010
Here's more proof that the soybean is an amazing, yet complicated plant. According to researchers who did genome sequencing, soybeans have some 46,000 genes. They're the pieces of protein that carry traits.

To give you an idea of how complicated deciphering the genetic code for soybeans were, the abstract for a scientific article to be published in a scientific journal, Nature, last week contained 40 names as authors. Many are graduate students. Typically, an article in a scientific journal has two to six authors.

Scott Jackson, one of the researchers, said that the genome has traits that make it especially tough to sequence. Many of those 46,000 genes, maybe as many as 70 to 80%, are duplicates. Therefore, some genes within the soybean genome have multiple copies within the genome.

The team also discovered that the soybean genome contains features not yet found in any other genome scientists have studied. The new feature, called TEs, or transposable elements, are largely 'junk' one scientist says. Yet some are important, and likely influence how genes perform. This discovery was considered so important that the team published a separate article in The Cell, another scientific publication, that was out last Friday, Jan.15.

The research team hopes that having the genome sequenced will prove to be a major step forward toward comparing different varieties of soybeans. The goal is to determine which genes are responsible for various characteristics. These characteristics range from oil content to the size of the plant.

This project is just the beginning, not the end, researchers say. Now their goal is to resequence some 20,000 soybean line sin eh U.S. germplasm supply. The search will be for genes not common to all soybean varieties.

The team of researchers suspect that valuable traits may have been left behind through the selection process for improved varieties of soybeans. As plant breeders domesticated soybeans over the years, they selected for seed size and other agronomic traits. However, Jackson and others believe that valuable proteins associated with such factors as protein content of disease resistance may have been left behind,.

Checkoff dollars from the Untied Soybean Board help support this work. The national Science Foundation and both USDA and the Department of Energy also helped fund this research effort.

One co-author does his work at Iowa State University. 'What used to take literally years can take weeks or months now," Randy Shoemaker concludes.